Application of the state-space model to oscillating buoy hydraulic system′s absorbing device

The state-space model is one of the effective mathematical models to study the interaction between ocean waves and the wave energy conversion system.One of the key aspects of the application of the model is how to efficiently obtain the matrix parameters of the model according to the experimental data or the computed values of the impulse response function.In combination with the brachistochronic method,the least square method and the precise integration method,the matrix parameter is computed.Two methods are adopted in this paper to simulate the displacement,the velocity,and the acceleration of cylinder derived in the presence of the wave energy absorbing device,and to compute the absorbing power of the wave energy device in the nonlinear damping condition so as to achieve the optimal design parameter.